Respirator



Nov. 2l, i939. N. stl-lwARTz REsPIRAToR Filed Nov. 15, 1956 l... @Illu-lm #Illa r 1 Patented Nov. 21, 1939 Unirse ,STATES REsPmA'roiz,l

Nathan s chwartz, New Yra'N. Y. Application November 13, 1936; Serial No. 110,557 i oiain'fis. (cifras- 146) t This invention relates to filter type respirators adapted to cover the nose and mouth ofy the wearer for the purpose of protection against dust, fumes and injurious gases, and is a modification of my copending application for Letters Patent, Serial No. 44,694, filing date October 12, 1935 now Patent No. 2,070,241, of February 9, 1937.

The invention broadly aims to provide a respirator of minimum size and weight, while af- 1.0.A forcling a maximum area of filtration, and is so constructed at connecting points as to make it leak proof, and also aiords convenient locations for attached filter units and also for exhalation valve, and provides for easy replacement of filter materials. f

More particularly the invention resides in so placing the filter yunit as to `cause no annoyance to the wearer. Namely a special connecting tubeV is provided at the set back portion below the 20." nose line for attachment of the filter unit andv Another object is to make theconnection at the head band and the face piece air tight and Another object is to make the connection at the marginal attachment of the filter element leak proof and at the same time easily replaceable.

Another object is to minimize the air spaces in the face covering portion, the 'filter unit and also in the connecting duct or tube. It is for that reason that one tube is made suitable for the attachment of both the filter unit and the exmilation valve. v

With the above recited and other objects in View, reference is had to the following description and accompanying drawing, in which there 45,* is exhibited one example or embodiment of the invention, while the claimsl define the actual scope of the same.

In the drawing: Figure l is a side View of the respirator, showing the attachment of the elastic head or neck band to the face piece of the respirator and also sho-wing the location of the lter units and exhalation valve. v v

" is a front View and the front filter Figure a unit is illustrated, showing its connection to the downwardextending tubular or duct member, located below the nose line.

Figure. 3 'is a cross 'section at line 3`3 of Figure 2 and illustrates the filter 'material' attachment and also the filter unit attachment at' the suspended tubular part, and also the exlialationv attachment at the lower portion of said' tubular suspension. l

Figure 4 is al crosstsection of the filter unit which is 'attached to the mouth and chin coveringwall. 'l iv Figure 5 is across section at point 5-5of Figure` 1, and illustrates' the attachment of the elastic head band to the face piece of the respiraton Figure 6 isa perspective View of the attachment of the headband to the face piece of the respirator and shows the partsjsep'arated.

Figure 7 is arear view of the respirator. Referring to the drawing byr characters `of reference, A Vdesignates the face. piece of the I respirator, B designates the lter unit, C' designates the exhalation Valve', and Djdesignates the elastic heady bands. Y

The facepiece `A of the respirator is constructed of molded elastic rubber or its equivalent, and it is to be understood that the construction' may be of other lmaterial such as aluminum oir its equivalent. The preferred material is of molded semi-flexible rubber. For attaching` vthe elastic head band a slit I0 is madey at both sides of the facepiece I0 of 'therespirator and the free end II'l of the head band Dis drawn through the said slit, swatches I2 of sheeting rubber is placed over-the slits Ill, the free end II and the face` piecev D lin the surrounding areay if the slit IQ. The said-swatches I2 Vare placed in covering relation to the said mentioned parts and adhesivev 1y attached one to another.` The free end II of the head band is folded I3 and is turned to overlap the face piece A of the respirator on the opposite'side t'o'where itl was inserted. It is to be understood that the insertionA of said free end may be made from kthe outside .or from the inside. The swatches I2 are preferably emplacedV and attached after the free end Il is folded I3 and therefore rthesaid swatches I2 are preferably covering the free end Ilwhen in a folded position;l However it must beunderstood that a very ,good connecting attachment may be made without folding the free end II. That is, merely insertingv said free end` I I into thev slit and leaving it unfolded and Vthus emplacing and attaching the swatches I2. In this'instance the free end II would also be at the opposite side of the face piece to whereit was inserted, but the said free end would be pointing forward instead of rearward. l i

This method of attaching head bands to respirators is an improvement because leaking possibilities are thereby entirely eliminated and also a smoother face engaging margin at the area of head band attachments is thereby provided, which makes the respirator more comfortable to the wearer.

The face piece A of the respirator has a set back I4 which set back is formed providing a recess I5 below the nose line. The said recess creates a verticalv nose covering portion I6, and*` a horizontal nose covering portion I5 and a chin and mouth covering portion I'I. The recess' I5 is the same as the horizontal nose covering portion I5. The horizontal nose covering portion I5 has a suspended duct or tubular attachment I8. The said tubular part is preferably oval shaped and may be integral with the horizontal nose covering part or may be a separate tube or duct and connected to the said horizontal nose covering part I5. 'Ihe filter unit B is attached by means of an eyelet I9 to the anterior aspect of the suspended tube I8. An opening perforation 2|) is provided in the anterior aspect of the suspended tube I8 and the said opening 20 registers with a similar opening perforation 2| in the filter unit and the eyelet I9 provides sealed connection. The said eyelet I9 is a stiff tubular element with the edges everted at both ends whereby outwardly directed flanges are formed, and these flanges clamp the apertures of the filter plate and the suspended tube forming a leak proof joint thereat. The suspended tube I8 has attached at its lower portion an exhalation flap valve C, which is of the accepted army type exhalation flap valve and sometimes called flutter valve. The method of the attachment of said valve C is as follows. A metal tube 22 is inserted in the lower opening 23 of the suspended tube in order to permanently hold open the said lower end and then the proximal end 24 of the valve is slipped over the lower end 23 of the suspended tube and cemented thereon.

When the concentration of the dust, gases or fumes to be filtered is low the single filter unit with the attached exhalation valve is sufficient for the filtering and separating such dust fumes and gases. But when the concentration of such dust fumes' and gases is high, there is need of higher resisting filter material and consequently a larger filtering area is to be provided. Therefore we provide in this invention a second filteringmaterial which is attached to the wall I'I, namely the wall that covers the mouth and chin. Two of these filter units may be conveniently attached as is illustrated in Figure 1. These are located one behind the other. The said position is advantageous because an additional iilt'er unit is provided in the same area with almost no extra space and therefore without any hindrance to vision or to movements of the head. It is to be noted that the metal tube 22 which is inserted at the lower end 23 of the suspended tube I8 provides a safe separation between the two lter units and also provides an unobstructed action for the exhalation valve C.

Therefore when the injurious matter to be filtered is of high concentration another filter unit is provided at the wall I'I.v 'Ihe said wall I'I has an opening 25 and the said opening 25 registers with the opening 2| ofthe filter unit and an eyelet I9 provides a leakproof connection. The said eyelet I9 is a stiff tubular ele- I ment with the edges everted at both ends whereby outwardly directed fianges are formed which fianges clamp the filter unit and the face piece at the openings 2| and 25 and thereby provides a leak proof joint thereat.

The filter unit B is preferably of aluminum or an equivalent metal or it may be in certain instances of semi-flexible molded rubber. The inside wall of the filter unit is provided with button elevations 26, which elevations define grooves 21 for the unobstructed flo-w of air. That is at inspiration the air passes the lter material and its next' passage is the continuousI air channel 2'I. The said air channel leads the filtered air to the filter unit opening 2| and the filtered air then passes to the face piece A and then to the respiratory organ of the wearer.

Flanged means are provided at the margins of the lt'er unit for impinging upon the filter material so that unfiltered air shall not pass at the connection of the filter material 28 and the said impinging flange. 'Iwo forms of such flanged margins are here shown. First form is an interned flange 29. This interned flange illustrates a hook shaped fia-nge which is very emcient. The applicants Letters Patent for Separator for filter type respirators or the like, No. 2,035,097, illustrates' another form of interned flange for impinging effectively upon a filter material. It is to be noticed that the hook formation is inward and then upwards. The terminal end of the fiange is preferably smooth and rounded, so that the filter material may be easily removed.

Another form of flange 30 is practicaland is equally efficient, namely the fiange 3!) is inwardly directed as illustrated in Figure 3 and a washer 3| of rubber or of an equally firm material is inserted at the inner side of the interned flange. The said washer is naturally the same size as the fiange and is to fit correctly. The said washer 3| is adhesively attached to the inner side of the flange 30.

The filter unit elevations are formed by stamping dents 32 at the outer side of the filter unit wall or it may be formed by attaching to the inner side of the said wall several elevating niaterials such as button or rib shaped metal or hard rubber. The latter form is not shown in the drawing.

It is to be understood that' more than one ai:` duct or oval tube I8 may be suspended at the horizontal nose covering portion and exhalation valves or filter units may be attached thereto. That is, when the fumes are very dangerous to health further protection is required, and the respirator in such an instance must have greater efficiency. To provide additional efficiency the filter material used necessarily must have a greater resistance to air flow and that makes breathing difficult. In adding lter units the filtration area is increased. 'I'he advantage of adding multiple lter units instead of enlarging a single one or two lter units is that one or even two filter units would be too clumsy and inconvenient if the enlargement is made sufficient to provide the large filtering area necessary for dangerously poisonous fumes or gases. Therefore one, two or three oval tubes I8 may be suspended from the said horizontal wall I5, for construction and provision of greater safety against poisonous dust, fumes or gases. In the drawing only one oval tube is shown. If two such tubes I8 are required the horizontal wall I5 would need have a larger antro-posterior diameter. That is, suiciently largeto accommodate the additional tube I8, The tube or air passage duct I8 is preferably oval shaped but it may vary and be square shaped or other shape, but must be able to accommodate at its anterior vaspect a lter unit and when so required to accommodate a flap valve at its end. l

It is to be understood that the connection of the head band D and the hollow mask body A may be accomplished without swatches. That is the free end ll of the head band is inserted into the slit I which slit I0 is to be somewhat smaller in length than theinserted width of the free end H and thereby providing a tight lit. When this arrangement is made the application of ad.

hesive cement produces an air tight connection. Additional rmness is provided by applying the swatches I2 and also adhesively attaching them as heretofore described. In the drawing, Figure 6 shows the swatches distantly and thereby i1- lustrating the vappearance of the head band connection without overlapping swatches.

Having thus described my invention I claim as new and desire to secure by Letters Patent: 1. In a respirator, a face piece having an intake port, a filter unit including a wall having an outlet port and a means connecting the filter unit to the said face piece and establishing cornmunication therebetween through said inlet and outlet ports comprising a tubular air duct having apertures with the tubular Wall of said conduit being parallel with the said wall of the filter unit and one of said apertures connects with the lt'er unit while another aperture connects with the face piece and the said filter unit confronts the said face piece and is spaced therefrom b-y the said air duct. v

2; A respirator having a hollow mask body provided with a recess below the nose line and at least two lt'er units each of which is provided with an-independent air chamber and the said chambers are connected with the body of the respiratorr at the said recess portion and means provided to maintain a spaced relation between the said lter units.

3. A respirator having a hollow mask body provided with several filter units each of which isprovided with an independent air chamber and the said units are located in antro-posterior alignment.

4. A respirator including a face piece having head band attachments for securing the respirator to the face of the wearer and the said face piecebeing connected with lter units and an exhaust valve at a recessed portion below the nose line, and one of the said filter units connects with the said face piece by means of an air,` duct, while another filter unit connects with the said face piece at the vertical wall ofsaid `recessed portion, and the said lilter unitshave and the said lter units are in confronting rela- NATHAN SCHWARTZ` 

